Decarborane derivatives containing two hydrocarbyl radicals and a group v-a element and their preparation



United States Patent 3,013,041 DECARBORANE DERIVATHVES CONTAINING TWO HYDROCARBYL RADICALS AND A GROUP V-A ELEMENT AND THEIR PREPA- RATION Victor I). Aftandilian, Wilmington, DeL, assignor to E. I. du Pont de Nernours and Company, Wilmington, Del., a corporation of Delaware No Drawing. Filed Get. 29, 1959, Ser. No. 849,459 12 Claims. (Cl. 260-440) This invention relates to novel derivatives of decaborane and to their preparation. -More particularly, this invention relate to such derivativescontaining certain elements of group V-A of the periodic table and to a process for their preparation.

Boron compounds have received considerable study during recent years and during this time the boron hydrides, including decaborane, have been found useful in various applications. Particular applications for these boron hydrides and their derivatives that have been developed include high energy fuels and chemical reducing agents. It is therefore a desirable goal to provide new decaborane derivatives having particular characteristics that make them especially useful in these and other applications.

It is an object of this invention to provide novel derivatives of decaborane and a process for their preparation. A further object is to provide a new class of decaborane derivatives containing certain elements of group V-A of the periodic table. Other object will appear hereinafter.

These and other objects of this invention are accomplished by providing novel products having the general formula R2MB1QH13, wherein the Rs are monovalent hydrocarbyl and the two Rs can be the same or different, and M is an element of group V-A of the periodic table having an atomic number not greater than 51, i.e., nitrogen, phosphorus, arsenic or antimony. A preferred group of the products of this invention is that in which the Rs in the above general formula are alkyl or aryl radicals of not more than 10 carbon atoms. The periodic table referred to in this application is the table given in Demings General Chemistry, 5th ed. (1944), John Wiley and Sons, Inc.

The products of this invention are prepared by reaction of an ethereal solution of the Grignard derivative of decaborane (B H MgX', where X is halogen of atomic number of at least 17, i.e., chlorine, bromine or iodine) with a compound of the formula R MX, wherein the R groups are monovalent hydrocarbyl radicals, i.e., monovalent hydrocarbon radicals, which can be the same or difierent, M is an element of roup VA of the periodic table having atomic number no greater than 51, and X is a halogen. The preferred halogen in the R MX compound has an atomic number of at least 17, i.e., is chlorine, bormine or iodine.

The reaction between the B H MgX and the RQMX is carried out with equimolar quantities of reactants in an ether reaction medium. Any ether that can be used in preparing a Grignard reagent is suitable as a reaction medium in the process of this invention. Examples of suitable ethers include tetrahydrofuran and dialkyl ethers, such as diethyl ether, di-n-propyl ether, and di-n-butyl ether.

The reaction can be carried out at atemperature ranging from about 0 to 150 C. or more but not above the decomposition temperature of any product or reactant. It is conveniently carried out at the reflux temperature of the particular ether being used as reaction medium, e.g., using diethyl ether as reaction medium, a reaction temperature of about 35 C. is convenient.

The reaction is continued for a period of time ranging M v 3,013,041 Patented Dec. 12, 1061 :lized from the petroleum ether solution. In some cases the products of this invention can be isolated by treatment of the reaction mixture with an approximately stoichiometrically equivalent amount of a saturated, aqueous am monium chloride solution to decompose the Grignard complex, after which the mixture is extracted with diethyl ether and the ether then removed by distillation or evaporation.

Dioxanates of the products of this invention can also be prepare-dif desired, by addition of dioxane to the reaction product obtained after decomposition of the Grignard complex by aqueous ammonium chloride.

The products of this invention are soluble in benzene and ethers, are only slightly soluble in aliphatic hydrocarbons, e.g., petroleum ether, and are insoluble in water. The products of this invention are chemical reducing agents and they are capable of reducing ions of silver and iron to the free metals.

The decaborane Grignard derivatives used as one of the starting materials in the process of this invention can be prepared by the method described in J. Am. Chem. Soc. 80, 4523 (1958). This method involves reaction of methylmagnesium iodide in ether solution with decaborane. The ether solution of the Grignard decaboranederivative can be used directly after removal of the by-product methane, and need not be isolated from the ether solution. The R MX starting materials can be made by kown methods. Thus, diphenylchloroarsine can be prepared by heating triphenylarsine with arsenic trichloride in an autoclave at 250280 C. for three hours, by the method described by Morgan and Vining, J. Chem. Soc., 117, 780 (1920). Diphenylchlorostibine can be prepared similarly from triphenylstibine and antimony trichloride. Diphenylchlorophosphine can be prepared by heating phenyldichlorophosphine at 300 C. for 96-120 hours, as described by Diirken, Ben, 21, 1505 (1888).

This invention is illustrated in further detail by the following examples in which the proportions of the in gredients are expressed in parts by weight unless otherwise specified. 1

EXAMPLE I Diphenylphosphinoaecaborane A 100-ml. flask equipped with a condenser and a side arm for introduction of liquids is attached to a vacuum train and 3.62 g. of decaborane (0.0296 mole) is placed in it. The flask is cooled with liquid nitrogen, evacuated to a pressure of 0.001 mm. of'mercury and 100 ml. of diethyl ether, dried over calcium hydride, is condensed into it. The flask is maintained at -196 C. while 12, ml. of a diethyl ether solution of methylmagnesium iodide (approximately 2.0 molar) is introduced into it.

and at the end of this time a clear, green-yellow solution is obtained. The diethyl ether is removed by vacuum distillation and 100 ml. of dry petroleum ether is condensed into the reaction vessel. The mixture is heated to boiling and filtered while hot to remove the insoluble magnesium halides. On cooling the filtrate, there is obtained 0.68 g. (10% of theory) of a white solid melting at 136-137 C. This is diphenylphosphinodecaborane.

Analysis.Calcd for (C6H5)2PB1DH13: B, Y P, 10.11%; C, 47.02%; H, 7.56%; M.W., 306. Found: B, 35.81%; P, 9.74%", C, 46.25%; H, 7.68%; M.W., 341.

Infrared analysis shows bands at 3.25, 6.3 and 14.45

microns which are assigned to =CH, aromatic-C=C- and monosubstituted aromatic groups, respectively.

There is a band at 3.95 microns representing the 13-11 function.

The diphenylphosphinodecaborane is soluble in ben zene, alcohol and ethers. It is insoluble in Water and very slightly soluble in aliphatic hydrocarbons. Its solutions reduce silver nitrate to metallic silver.

EXAMPLE ll Diphenylarsinodecaborane A solution of 0.0156 mole of decaborane magnesium iodide is prepared from 2.96 g. (0.0242 mole) of decaborane and 9 ml. of an approximately 2.0 molar diethyl other solution of methylmagnesium iodide by the procedure described in the first paragraph of Example I. The reaction vessel containing this solution is swept out with nitrogen and a ml. suspension of 4.10 g. of diphenylchloroarsine (0.0155 mole) in diethyl ether is added to it. The mixture is stirred and heated to C.

for 18 hours. At the end of this time a clear yellow solution is obtained. The diethyl ether is then distilled out of the reaction vessel and about 200 ml. of dry petroleum ether is condensed into it. The mixture is heated to boiling and filtered hot to remove insoluble magnesium halides. On cooling the filtrate, there is obtained 0.23 g. of white, solid diphenylarsinodecaborane. This compound decomposes at 180 C.

Analysis.Calcd for (C H ASB H Z As, 21.38%; C, 41.13%. Found: As, 22.76, 21.58%; C, 40.39%.

Theinfrared absorption spectrum of this compound is very similar to that of diphenylphosphinodecaboranc. The product is soluble in benzene, alcohol and ethers but is insoluble in water and only slightly soluble in aliphatic hydrocarbons. phenylarsinodecaborane reduce the ferric ion in ferric chloride to metallic iron and the silver ion in silver nitrate to silver metal. However, the alcoholic solutions do not reduce nickel ion to the free metal. The diphenylarsinodecaborane is hypergolic with nitric acid. The addition of concentrated nitric acid to the arsinic compound causes it to ignite spontaneously.

EXAMPLE Ill Dimethylaminodectzborane Following the procedure described in the first paragraph of Example I, 0.061 mole of the Grignard derivative of decaborane is prepared from methylmagnesium bromide and decaborane. The reaction vessel containing the ether solution of the decaborane Grignard derivative is swept out with nitrogen and 128 ml. of a solution of 0.04 mole of dimethylchloroamine in diethyl ether is added to it. The mixture is heated to the boiling point of diethyl ether and is stirred for 4 hours. At the end of this time a creamy yellow solid is obtained. The addition of 30 ml. of a cold, saturated, aqueous solution of ammonium chloride to the reaction mixture causes the decomposition of the Grignard complex. The resulting reaction product is extracted several times with diethyl ether and the ethereal extracts are dried over anhydrous calcium sulfate, A yellow oil is obtained on concen- Alcoholic solutions of the di-- tration of this solution. This oil is dimethylaminodecaborane. The addition of ml. of dioxane to this oil results in the formation of a yellow solid amounting to 0.62 g. and melting at 123-124 C. This is a dioxanate of dimethylaminodecaborane.

Analysis.-Calcd for (CH3)QNB1QH13'ZC4H8O2: B, 31.68%; N, 4.10%; C, 35.16%; H, 10.33%. Found: B, 32.62%; N, 4.44%; C, 31.19%;1-1, 10.65%.

In addition to the decaborane magnesium iodide and decaborane magnesium bromide illustrated in the Examples, decaborane magnesium chloride can also be used in the process of this invention. Likewise, in addition to the specific R MX reactants illustrated in the examples, any compound of the general formula R MX in which the Rs are monovalent hydrocarbon radicals and the X is halogen, preferably chlorine, bromine or iodine, can be used in the process of this invention. In this process such compounds in which the R groups are alkylor aryl radicals of 1-10 carbon atoms are preferred. Thus, when the specific R MX compounds listed in thefirst column of the following Table Iare reacted with a decaborane magnesium halide, the products listed in the second column of this table are obtained.

TABLE I RzMX Product (QHQQPCI (CaHalzPBrpHra Dicthylchlorophosphlue Dlethyl ihosphinode-can-oiunmsr (n mAsBmHu Dl-n-but yhodoai sine D1 n buty1 ms in o a e c (OaHnhSbCl borane Dihexylchlorostibine Di (oi u g sbgawrin (POHSOGHO 2P1 r exy s 1 mo eca crane \D QCsEAMP NUn Di-p-tolyhodophosphme Di p tolylphosphmodeca (n-Ol0Hll1)2PBl borane Di-n-decylbromophos- (n-CmHrOrPBmHrs phine Di-n-decy%)phosphinodeca- (onnmroi (0 10 82 131013111 i gg Dlnaphthyiphosphlnodecaborane (CH3) i -O HBNCzHQPBmYIu lvlethylethylbromophos- Methylethylphosphlnw phme (0113 66 3 3 H onmotueasnr 3 5 m Methylphenylbromoargggg sme fi 5)2NBmHi3 I (Calls) zNCl Dlphenylaminodeca- Diphcnylchloroamine borane The decaborane derivatives of this invention are useful in various applications. They are particularly useful as chemical reducing agents. As indicated in the examples, alcoholic solutions of these products are effective reducing agents in reducing silver and ferric ions 'to metallic silver and iron.

The/products of this invention also ignite spontaneously when contacted with concentrated nitric acid. This is a valuable property which makes them useful as high energy fuels.

As many apparently widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that this invention is not limited to the specific embodiments thereof except as defined in the appended claims; v

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A' compound having the general formula 2 m 1s wherein each R is selected from the group consisting of alkyl radicals and aryl radicals and M is an element of group V-A of the periodic table having an atomic number not greater than 51.

2. A compound having the general formula R2MB1UH13 wherein each R is an alkyl radical of not more than 10 carbon atoms and M is an element of group V-A of the periodic table having an atomic number not greater than 51.

3. A compound having the general formula wherein each R is an aryl radical of not more than 10 carbon atoms and M is an element of group V-A of the periodic table having an atomic number not greater than 51.

4. Diphenylphosphinodecaborane.

5. Diphenylarsinodecaborane.

6. Dimethylaminodecaborane.

7. Process of preparing a decaborane derivative which comprises contacting and reacting, in an ether reaction medium, a compound having the formula B H MgX' wherein X is halogen having an atomic number of at least 17 with a compound having the formula R MX wherein each R is selected from the group consisting of alkyl radicals and aryl radicals, M is an element of group V-A of the periodic table having an atomic number not greater than 51, and X is halogen.

8. Process of preparing a decaborane derivative which comprises contacting and reacting, at a temperature within the range of 0-150 C. in an ether reaction medium, a compound having the formula B H MgX wherein X' is halogen having an atomic number of at least 17 With a compound having the formula R MX wherein each R is an alkyl radical of not more than 10 carbon atoms, M is an element of group V-A of the periodic table having an atomic number not greater than 6 51, and X is halogen having an atomic number of at least 17.

9. Process of preparing a decaborane derivative which comprises contacting and reacting, at a temperature within the range of 0150 C. in an ether reaction medium, a compound having the formula B H MgX wherein X is halogen having an atomic number of at least 17, with a compound having the formula R MX wherein each R is an aryl radical of not more than 10 carbon atoms, M is an element of group V-A of the periodic table having an atomic number not greater than 51, and X is halogen having an atomic number of at least 17.

10. Process of preparing diphenylphosphinodecaborane which comprises contacting and reacting, at a temperature within the range of 0-150 C. in an ether reaction medium, decaborane magnesium iodide with diphenylchlorophosphine.

11. Process of preparing diphenylarsinodecaborane which comprises contacting and reacting, at a temperature within the range of 0150 C. in an ether reaction medium, decaborane magnesium iodide with diphenylchloroarsine.

12. Process of preparing dimethylaminodecaborane which comprises contacting and reacting, at a temperature within the range of 0-150" C. in an ether reaction medium, decaborane magnesium bromide with dimethylchloroamiue.

No references cited. 

1. A COMPOUND HAVING THE GENERAL FORMULA 